An Associated Press investigation revealed that Myanmar's military uses systematic torture on detainees across the country since it took over the government in February.

An estimated 1,200 people have been killed by security forces, including around 131 tortured to death.

The military has also abducted thousands, including young men and boys, has used the bodies of the dead and wounded as tools of terror, and has deliberately attacked medics during the pandemic.

A monk was made to hop like a frog in a humiliation tactic, an accountant was shocked with electric probes, an artist was beaten in the head with a baton until he passed out – the list goes on.

Speaking with 28 people imprisoned and released in recent months, and based on photos, sketches, letters, along with testimony from three army defectors, the AP investigation provided an inclusive look into a highly secretive detention system that has held more than 9,000 people and terrorised many more.

Hundreds of people rallied on March 3 in Yangon to protest the military takeover.

When the military moved in, firing tear gas and sound grenades, the protesters fled, but they were pursued by the army, which eventually detained 400 people.

Detainees were packed into trucks, with some being taken to interrogation sites in Yangon.

Myanmar journalist Nathan Maung spent several months in one of the southeast Asian country's prisons before he was released in June.

Maung compared his experience in a Yangon interrogation site to hell. He described being beaten repeatedly. "It was so painful," he said.

"Whenever I answer and if they don't like it, then the guys standing on my left would hit my face and hit my head," Maung revealed.

"The interrogation centre is like Hell. Every day, every minute, you never know, you cannot say what is going to happen to you," he went on.

The AP identified a dozen interrogation centres in use across Myanmar, in addition to prisons and police lockups. These findings are based on prisoner testimonies and satellite photo analysis.

Matthew Smith, CEO of Fortify Rights, a human rights NGO, said torture is widespread in Myanmar.

"Torture is occurring nationally by both the police and the military. It's happening in cities, it's happening in villages, it's happening in the central plains, in the ethnic highlands, in various locations. All of these facts indicate to us the widespread and in some ways, systematic nature of the torture that's occurring in the country right now," Smith added.

While men face more severe physical torture, women are more often psychologically abused, especially with the threat of rape.

The Myanmar military has a long history of torture, particularly before the country began transitioning toward democracy in 2010.